Liquid crystal display with display screen extending out of casing

ABSTRACT

An exemplary liquid crystal display (LCD) includes a casing and a liquid crystal panel accommodated in the casing. The casing includes a frame and a window surrounded by an inner side of the frame. The liquid crystal panel includes an outside surface essentially serving as a display screen for displaying images and a peripheral wall. The liquid crystal panel is attached to the frame, with the inner side of the frame contacting the peripheral wall of the liquid crystal panel, and the display screen exposed outside of the casing.

BACKGROUND OF THE DISCLOSURE

1. Field of the Disclosure

The present disclosure relates to liquid crystal displays (LCDs), andmore particularly to a liquid crystal display having a display screenextending out of a casing.

2. Description of Related Art

An LCD has advantages of portability, low power consumption, and lowradiation, and has been widely used in various portable informationproducts such as notebooks, personal digital assistants (PDAs), videocameras and the like. A typical LCD includes a casing and a liquidcrystal panel accommodated in the casing. The liquid crystal panelincludes a thin film transistor (TFT) substrate, a color filter (CF)substrate opposite to the TFT substrate, a liquid crystal layersandwiched between the two substrates, and a sealant surrounding theliquid crystal layer. The sealant is coated on a peripheral region ofthe TFT substrate, and is sandwiched between the two substrates. The twosubstrates and the sealant cooperatively define a space foraccommodating the liquid crystal layer. Silver beads are provided at anoutside of the sealant, and electrically connect the two substrates.

The LCD may be used in an environment where temperatures alternatebetween hot and cold. Under such conditions, shadows may appear at aperiphery of a display area of the liquid crystal panel. This problem iscommonly known as the black-sun phenomenon. In addition, slightcorrosion may also appear at the positions where the silver beads arelocated. Thus the display quality of the LCD is impaired.

What is needed, therefore, is an LCD which can overcome the describedlimitations.

SUMMARY

An exemplary liquid crystal display (LCD) includes a casing and a liquidcrystal panel accommodated in the casing. The casing includes a frameand a window surrounded by an inner side of the frame. The liquidcrystal panel includes an outside surface essentially serving as adisplay screen for displaying images and a peripheral wall. The liquidcrystal panel is attached to the frame, with the inner side of the framecontacting the peripheral wall of the liquid crystal panel, and thedisplay screen exposed outside of the casing.

Other novel features and advantages will become more apparent from thefollowing detailed description when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The components in the drawings are not necessarily drawn to scale, theemphasis instead placed upon clearly illustrating the principles of atleast one embodiment. In the drawings, like reference numerals designatecorresponding parts throughout the various views, and all the views areschematic.

FIG. 1 is an isometric view of a liquid crystal display device accordingto a first embodiment of the present disclosure, showing part of theliquid crystal display device cut away.

FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1.

FIG. 3 is an isometric view of a liquid crystal display device accordingto a second embodiment of the present disclosure.

FIG. 4 is an isometric view of a liquid crystal display device accordingto a third embodiment of the present disclosure.

FIG. 5 is an isometric view of a liquid crystal display device accordingto a fourth embodiment of the present disclosure.

DESCRIPTION OF EMBODIMENTS

Reference will be made to the drawings to describe preferred andexemplary embodiments in detail.

In order to understand the reasons for the black-sun phenomenon of LCDs,repeated testing and verification have demonstrated the followingmatters, among others. The liquid crystal panel includes a major outsidesurface, which essentially serves as a display screen for displayingimages. The casing for accommodating the liquid crystal panel includes aframe which has a central window. The display screen of the liquidcrystal panel is viewable through the window. The frame includes a topsurface, and the elevation of the top surface is higher than the displayscreen. When the LCD is used in an environment where temperaturesalternate between hot and cold, dew appears on the display screen andgathers around the periphery of the display screen adjacent to theframe. This results in vapor of the dew being able to access theinterior of the liquid crystal panel and form a high-humidityenvironment in the liquid crystal panel.

In addition, a TFT substrate and a CF substrate of a typical liquidcrystal panel are electrically connected to each other via silver beads.The silver beads pass through holes in an insulating layer of the TFTsubstrate to electrically connect with metal circuits which are locatedunder the insulating layer. When the interior of the liquid crystalpanel has the high-humidity environment, the holes in the insulatinglayer expose the metal circuits to the vapor. In particular, portions ofthe metal circuits adjacent to the silver beads become high-risklocations subject to corrosion. When this happens, the adhesion of thesealant may be impaired. Thus, shadows may appear on the periphery ofthe display screen, and the display quality of the liquid crystaldisplay device is reduced.

In this description, a reference to “dew” can include a reference tomoisture in general.

Referring to FIG. 1 and FIG. 2, schematic views of a liquid crystaldisplay device according to a first embodiment of the present disclosureare shown. The liquid crystal display device 200 includes a casing 220,and a liquid crystal panel 210 accommodated in the casing 220. Thecasing 220 may be made of plastic material.

The liquid crystal panel 210 includes a first substrate 212, a secondsubstrate 214 opposite to the first substrate 212, and a liquid crystallayer (not labeled) sandwiched between the two substrates 212, 214. Thefirst substrate 212 may be a TFT substrate, and the second substrate 214may be a CF substrate. A sealant 213 is coated on a peripheral region ofthe first substrate 212, and is sandwiched between the two substrates212, 214. The sealant 213 surrounds the liquid crystal layer. The twosubstrates 212, 214 and the sealant 213 cooperatively define a spaceaccommodating the liquid crystal layer. A plurality of conductiveadhesives 216 (only two shown) is provided at an outside of the sealant213, and electrically connect the two substrates 212, 214. Eachconductive adhesive 216 is generally in the form of a discrete bead. Inthe illustrated embodiment, each conductive adhesive 216 isapproximately cylindrical. The beads include at least one silver-basedcompound, which includes silver grains. The liquid crystal panel 210 hasa major outside surface, which essentially serves as a display screen(not labeled) that shows images viewed by users. In particular, theoutside surface of the second substrate 214 essentially serves as thedisplay screen.

The casing 220 includes a frame 222, and a window (not labeled)surrounded by the frame 222. The liquid crystal panel 210 is attached tothe frame 222, with the display screen extending through the window, andan inner side of the frame 222 contacting the peripheral area of theliquid crystal panel 210. That is, the display screen passes through thewindow and protrudes out from the window. The frame 222 includes a topsurface 224, and an elevation of the top surface 224 is lower than anelevation of a top of the display screen. Thus, there is a distance Hdefined between the top surface 224 of the frame 222 and the displayscreen. That is, the display screen of the liquid crystal panel 210extends out of the casing 220 from the window.

In use, when the liquid crystal display device 200 is in an environmentwhere temperatures alternate between hot and cold, dew occurring on thedisplay screen may include dew on the peripheral area of the displayscreen. Because the elevation of the top surface of the frame 222 islower than that of the top of the display screen, at least some of thedew on the peripheral area of the display screen can drain down to thetop surface of the frame 222. Therefore the dew is spread over a largerarea, and can more easily evaporate off.

In the above-described conventional art, dew is liable to gather arounda periphery of the display screen where the periphery of the displayscreen adjoins a frame. That is, dew is liable to gather at avapor-permeable interface between the display screen and the frame. Incontrast, in the present embodiment, the amount of dew present at (a topof) an interface between the frame 222 and the liquid crystal panel 210is relatively little. As a result, the risk of vapor of the dewpenetrating the interface between the frame 222 and the liquid crystalpanel 210 is relatively low. A high-humidity environment is apt to notbe formed in the liquid crystal panel 210, and corrosion within theliquid crystal panel 210 is avoided. Thus, the LCD 200 can work normallyand reliably.

Referring to FIG. 3, an LCD 300 according to a second embodiment of thepresent disclosure is similar to the LCD 200 of the first embodiment.However, in the LCD 300, at least one groove 324 is provided in a frame322 of a casing 320. In the illustrated embodiment, there are aplurality of the grooves 324. Each groove 324 may have a rectangularshape. Each groove 324 is positioned corresponding to a respective oneof a plurality of conductive adhesives 316 (only two shown) of a liquidcrystal panel 310. Thus portions of the liquid crystal panel 310 havingmetal circuits adjacent to the conductive adhesives 316 are also locatedcorresponding to the grooves 324. Each groove 324 can act as a kind ofdew sink, and dew collected in the groove 324 is spread over arelatively large area at a bottom of the groove 324. Therefore the dewcan more easily evaporate off. As a result, the risk of the dewpenetrating an interface between the frame 322 and the liquid crystalpanel 310 is relatively low. A high-humidity environment is apt to notbe formed in the liquid crystal panel 310, and corrosion within theliquid crystal panel 210 is avoided. Thus, the LCD 300 can work normallyand reliably. Moreover, the advantageous grooves 324 are positionedwhere the risk of corrosion would otherwise be highest—at the conductiveadhesives 316.

Referring to FIG. 4, an LCD according to a third embodiment of thepresent disclosure is similar to the LCD 300 of the second embodiment.However, each of grooves 424 has a trapezoidal shape.

Referring to FIG. 5, an LCD according to a fourth embodiment of thepresent disclosure is similar to the LCD 200 of the second embodiment.However, each of grooves 524 runs through an entire transverse width ofa frame.

The LCD herein is not limited to the above-described embodiments. Forexample, the frame may include a plurality of grooves, wherein some ofthe grooves have a rectangular shape, and other of the grooves have atrapezoidal shape. The quantity and the shapes of the grooves can beconfigured according to particular requirements.

It is believed that the present embodiments and their advantages will beunderstood from the foregoing description, and it will be apparent thatvarious changes may be made thereto without departing from the spiritand scope of the invention or sacrificing all of its materialadvantages, the examples hereinbefore described merely being preferredor exemplary embodiments of the invention.

1. A liquid crystal display (LCD), comprising: a casing comprising aframe and a window surrounded by an inner side of the frame; and aliquid crystal panel held in the casing, the liquid crystal panelcomprising: an outside surface essentially serving as a display screenfor displaying of images; and a peripheral wall; wherein the liquidcrystal panel is attached to the frame, with the inner side of the framecontacting the peripheral wall of the liquid crystal panel, and thedisplay screen exposed outside of the casing.
 2. The LCD as claimed inclaim 1, wherein the frame further comprises a top surface, the displayscreen passes through the window to extend over the top surface of theframe.
 3. The LCD as claimed in claim 2, wherein the liquid crystalpanel comprises a TFT substrate and a CF substrate opposite to the TFTsubstrate, a sealant is coated on a peripheral region of the TFTsubstrate, and is sandwiched between the TFT and CF substrates, the twosubstrates and the sealant cooperatively define a space foraccommodating a liquid crystal layer.
 4. The LCD as claimed in claim 3,wherein a conductive adhesive is provided at an outside of the sealant,and electrically connects the two substrates.
 5. The LCD as claimed inclaim 4, wherein the conductive adhesive is provided in a form ofdiscrete beads, the beads comprises at least one silver-based compoundwith silver grains.
 6. The LCD as claimed in claim 5, wherein the framecomprises at least one groove corresponding to the conductive adhesive.7. The LCD as claimed in claim 6, wherein the at least one groovedefines a rectangle profile.
 8. The LCD as claimed in claim 6, whereinthe at least one groove defines a trapezium profile.
 9. The LCD asclaimed in claim 6, wherein the at least one groove along the directionperpendicular to the display screen runs through the frame.
 10. The LCDas claimed in claim 5, wherein the frame comprises a plurality ofgrooves, part of the grooves define a trapezium profile, and part of thegrooves define a trapezium profile.
 11. A liquid crystal display (LCD),comprising: a frame comprising a top surface; an opening surrounded byan inner periphery of the frame; and a liquid crystal panel, the liquidcrystal panel including a display area and a peripheral mounting wall,wherein the liquid crystal panel is attached to the frame, with themounting wall attached to the inner periphery of the frame, and thedisplay area exposed beyond the opening above the top surface of theframe.
 12. The LCD as claimed in claim 11, wherein the liquid crystalpanel comprises a TFT substrate and a CF substrate opposite to the TFTsubstrate.
 13. The LCD as claimed in claim 12, wherein a sealant iscoated on a peripheral region of the TFT substrate, and is sandwichedbetween the TFT and CF substrates, the two substrates and the sealantcooperatively define a space for accommodating a liquid crystal layer.14. The LCD as claimed in claim 13, wherein a conductive adhesive isprovided at an outside of the sealant, and electrically connects the twosubstrates.
 15. The LCD as claimed in claim 14, wherein the conductiveadhesive is provided in a form of discrete beads, the beads comprises atleast one silver-based compound with silver grains.
 16. The LCD asclaimed in claim 15, wherein the frame comprises at least one groovecorresponding to the conductive adhesive.
 17. The LCD as claimed inclaim 16, wherein the at least one groove defines a rectangle profile.18. The LCD as claimed in claim 16, wherein the at least one groovedefines a trapezium profile.
 19. The LCD as claimed in claim 16, whereinthe at least one groove along the direction perpendicular to the displayscreen runs through the frame.
 20. The LCD as claimed in claim 15,wherein the frame comprises a plurality of grooves, part of the groovesdefine a trapezium profile, and part of the grooves define a trapeziumprofile.